In radio or wireless LAN (Local Area Network) internationally prescribed by IEEE (The Institute of Electrical Electronics Engineers, Inc.) 802.11, radio stations connected to wire network are distinguished in the state where specific functions are provided as access point.
Access points carry out management of plural other radio stations existing within the range where radio communication can be made (hereinafter referred to as service area) and plural communication terminal equipments connected to the access points themselves by wire. In this case, other radio stations are independent of management of plural access points. When management of the radio station is carried out by plural access points, there takes place inconvenience in communication by loop formation, etc. For this reason, in the radio or wireless LAN that the IEEE 802.11 prescribes, management of the radio station is carried out only by a certain one access point within the same service area. Namely, the data station is logically separated from other radio stations existing in the service area that other access points carry out management.
Access point can transmit communication data packet which has been caused to undergo transmission from communication terminal equipment connected to the access point itself by wire to other radio station that the access point itself carries out management. Alternatively, access point can transmit communication data packet which has been caused to undergo transmission from radio station that the access point itself carries out management to communication terminal equipment connected to the access point itself by wire.
In the radio LAN prescribed by IEEE 802.11, access points and radio stations caused to undergo management by the access points univocally correspond to each other. For this reason, in the radio LAN standardized by IEEE 802.11, in the case where one of communication terminal equipments connected to network that one access point carries out management carries out communication between the above-mentioned one access point and one of communication terminal equipments connected to network that other access point carries out management, access points are connected to each other by wire to thereby prevent occurrence of loop, etc. and to attain communication between mutual communication terminal equipments.
As described above, in the radio or wireless LAN standardized by the IEEE 802.11, in order that radio stations under control (management) of separate or different access points attain communication, it is necessary to connect access points to each other by wire.
However, in the case where there exist plural access points, it is troublesome work for user to connect these plural access points by wire. This problem can be solved by connecting access points to each other by radio. However, in the case where, e.g., one of communication terminal equipments connected to a certain access point is connected by wire to communication terminal equipment already connected to other access point, this network is connected by both wireless communication and wire communication. As a result, there is the possibility that communication data packet caused to undergo transmission on the network may form loop.